Electric dry shaver



Sept. 17, 1968 c, BAUER ELECTRIC DRY SHAVER 5 Sheets-Sheet 1 Filed May27, 1966 Ar wk \wu l K m wk In fen t 01 CHARLES L. BA UER Sept 17, 1968c. L, B E 3,401,453

I ELECTRIC DRY SHAVER Filed May-27, 1966 3 Sheets-Sheet 2 in /'en torCHARLEJ L. BAUER Sept. 17, 1968 c. L BAUER ELECTRIC DRY SHAVER 3Sheets-Sheet 3 Filed May 27, 1966 In fen for CHARLES L. BA (1512 UnitedStates Patent O 3,401,453 ELECTRIC DRY SHAVER Charles L. Bauer, CarolStream, Ill., assiguor to Sunbeam Corporation, Chicago, Ill., acorporation of Illinois Filed May 27, 1966, Ser. N0. 553,393

11 Claims. (Cl. 30-43.9)

ABSTRACT OF THE DISCLOSURE Electric shaver or other appliance having apair of parallel oscillating shafts of rectangular cross section. Eachof these shafts drives a separate cutter or other driven member. A powerunit is provided having motor means with a drive projection movabletoward and away from the parallel shafts. A unitary bifurcatedconnecting rod interconnects the projection and the two parallel shafts.This connecting rod is sufficiently resilient to permit flexing so thatno binding occurs. Spring means in the shape of a short handledmulti-tined fork having the handle portion secured to the rectangularshafts bias th cutters into shearing engagement with the perforatedcomb. The comb is defined by two joined arcuate perforated sections.

This invention relates to apparatus for removing beards or face hair aswell as hair on the arms, legs, and other portions of the human body,and is generally referred to as an electric dry shaver. Moreparticularly, the present invention is in the nature of an improvementon the electric dry shaver disclosed and claimed in Jepson et al. PatentNo. 3,196,539, granted July 27, 1965, and assigned to the same assigneeas the present invention. Moreover, certain features disclosed in thepresent application are also disclosed in copending applications, bothfiled of even date herewith, Ser. No. 553,510, Stahly et al., and Ser.No. 553,575, Bauer, both assigned to the same assignee as the instantapplication.

Electric shavers of several dififereut types are extensively employed bymany persons as the sole means of shaving. The type of electric shaverdisclosed in the abovementioned Jepson et al. patent has proven to beunusually satisfactory for reducing shaving time while still furnishinga very satisfactory shave. Moreover, this shaver has been designed sothat it may be held comfortably and conveniently in the hand of theoperator. A disclosed in this Jepson et al. patent, the electric dryshaver is pro- .vided with a plurality of oscillating cutter bladesmounted on an oscillating shaft and cooperating with a perforated comband depending upon centrifugal force and spring means for moving thecutters into shearing engagement with the comb. The oscillating shaftcarrying the cutter blades is connected through suitable cranks and aconnecting rod to a rotary motor.

More recently a cutting head has been developed which employs a pair ofsuch oscillating shafts, each of which carriesa plurality of oscillatingcutter blades cooperating with an arcuate portion of a perforated comb.It has been proposed to drive such a cutter head assembly from a rotarymotor my means of a pair of connectingrods each driven from a respectiveone of a pair of eccentric projections each extending from a gear drivenby a motor pinion, as more fully described in the above-identifiedStahly et al. application. However, it will be appreciated that althoughthe cost of any one driving arrangement may be small, neverthelesselectric dry shavers of this general type are produced in a very largevolume, and the consumer market for the sale of electric dry shavers ishighly competitive. Accordingly, it is desirable to provide an electricdry shaver which will compete favorably in price on the consumer market.In this regard it is de- Patented Sept. 17, 1968 sirable to provide adrive means interconnecting a rotary motor and a pair of oscillatingdrive shafts which may be manufactured and assembled at a minimum cost.

Moreover, in the design of a cutter head employing a pair of joinedarcuate comb surfaces, some difficulty may be experienced in maintaininga comparatively soft, flexible comb in the desired configuration.Further, in the consumer market it is important that the cutting bladesbe positively and economically secured to the'respective cutter shaft sothat the shaver may be economically produced and perform reliably forthe ultimate user.

Accordingly, it is an object of the present invention to provide a newand improved electric shaver.

It is another object of the present invention to provide a new andimproved electric shaver which overcomes the difiiculties mentioinedabove.

It is another object of the present invention to provide an electric dryshaver having an improved cutting head.

A further object of the present invention is to provide an electric dryshaver of the type having a pair of oscillating cutter shafts providedwith improved connecting means drivingly interconnecting the motor withthe respective oscillating shafts.

A still further object of the present invention is to provide a new andimproved cutting head assembly for a shaver.

It is another object of the present invention to provide an electricshaver which may be economically manufactured and assembled and whichwill provide foolproof operation.

Further objects and advantages of the present invention will becomeapparent as the following description proceeds and the features ofnovelty which characterize the invention will be pointed out withparticularity in the claims annexed to and forming a part of thisspecification.

For a better understanding of the present invention reference may be hadto the accompanying drawings in which:

FIG. 1 is an elevational sectional view through the cutter and casingportion only of an electric shaver embodying the present invention;

FIG. 2 is a fragmentary sectional view taken along line 22 of FIG. 1,assuming that FIG. 1 illustrates the entire shaver;

FIG. 3 is a fragmentary sectional view taken along line- 3--3 of FIG. 1,again assuming that FIG. 1 shows the entire shaver;

FIG. 4 is a fragmentary somewhat enlarged sectional view taken alongline 4-4 of FIG. 1, again assuming that FIG. 1 illustrates the entireshaver;

FIG. 5 is a sectional view taken along line 5-5 of FIG. 4, assuming thatFIG. 4 shows the complete structure; and

FIG. 6 is a perspective view of the cutter shaft, blade supports, andblade biasing springs of the shaver according to the present invention.

The present invention is particularly adapted for use with an electricshaver of the type having a shaving head unit including a uniformlycurved comb and an elongated cutter blade adapted to be moved along theinner surface of the comb in shearing engagement therewith. One featureof the invention is particularly adapted for use with an electric shaverhaving a double shaving head unit, that is, of the type having a combdefined by joined arcuate surfaces and including a pair of oscillatingcutter shafts each carrying one or more cutting blades for moving theits outwardly extanding legs for receiving the cutter blade.Additionally, there is provided an improved blade biasing spring whichmay be shaped like a short-handled multitined fork having the handleportion thereof secured to the fiat surface of the shaft in any suitablemanner as by welding, and having one of the tines each extending intothe path of a different one of the cutter blades.

In accordance with another feature of the present invention, there isprovided improved means for transferring power from a power unit todrive the pair of oscillating cutter shafts. It will be understood thatsuch oscillating cutter shafts, provided with an offset projectiondefining a crank, create a change in spacing between the cranks as theshafts oscillate. The shafts are driven from the power unit by a unitarybifurcated connecting rod defining a body portion connected to the crankor drive member of the prime mover, and provided with a pair of spacedarms each connected to a respective one of the cranks and sufficientlyresilient to permit flexing of the arms relative to each other as thecutter shafts oscillate. To provide the necessary resilience to the armsof the connecting rod, the arms may be provided with reducedcrosssectional areas adjacent the body portion of the connecting rod,and the connecting rod may be built of suitably resiilent material suchas nylon.

The single connecting rod with the bifurcated arms considerablysimplifies the connecting rod design providing an economicalarrangement. Moreover, the rectangular shaft cross section simplifiesthe connection to the shaft of both the blade supports and the bladesprings, thus reducing cost and simplifying assembly thereof.

Referring now to the drawings, the present invention is directed to anelectric shaver or shaving unit which includes a casing 21 defined by agenerally cup-shaped casing member 22 and a pair of end caps 24 and 25,all preferably molded from a suitable plastic. For supporting the motorand cutter described hereinafter, there is provided a support member 26which effectively closes the open top of the cup-shaped casing member 22to divide the casing 21 into a motor chamber below support 26, generallydesignated as 27, and a cutter chamber above the support 26 and betweenend caps 24 and 25, generally designated as 28. Disposed within thecutter chamber 28 is a cutting head assembly generally designated as 29.Disposed within the motor chamber 27 is an electric motor 30 secured tothe underside of the support member 26.

Considering the motor 30 in more detail, it may be of a known type suchas disclosed in copending Jepson et al. application Ser. No. 322,795,filed Nov. 12, 1963, and assigned to the same assignee as the instantapplication. As illustrated, motor 34) is of the rotating armature typehaving a generally U-shaped stator member 33, the ends of the legs ofthe stator member 33 having a somewhat arcuate configuration definingopposed pole pieces in a known manner. A field winding 34 is carried onthe bight portion of the stator member 33. A hanger bracket 35, as shownin the above-mentioned Jepson et al. application, and a pair of U-shapedbail clamps 37 and a bail hanger 38 hold the field structure in positionrelative to support 26.

The motor 30 includes an armature 39 having an armature shaft 40supported in suitable self-aligning spherical bearings in the mannerdescribed in the aforesaid Iepson et al. application. One end of thearmature shaft carries a commutator assembly 45, while the other endthereof is the crank end. Secured to the crank end of the armature shaft40 is an eccentrically mounted crank pin 46.

In order that a power connection can be made to the shaver 20 fordriving the motor 30, the casing member 22 is provided with a recess oropening 53 in its end adjacent its bottom defining a receptacle openingfor receiving a power connection. A terminal board 54 within the casing21 of the shaver 20 carries a pair of terminal members 55 extending intothe recess 53 for engaging co- 4 operating contacts of a power cord. Thelower end of the terminal board is keyed to an arm or projection 35a ofthe hanger bracket 35 so as to provide support for the terminal board54.

To provide a manual control for starting and stopping the motor 30, theterminal board 54 additionally supports a known electrical switch, showngenerally at 58. A manually operable switch knob 58a extends through anopening 24a in the end cap 24 to control the on-otf condition of theswitch 58.

Referring now to the cutting head unit 29, it includes a comb 60defining a cutting surface. Comb 60 comprises a pair of joined arcuateperforated sections 60a and 60b, FIGS. 3 and 4, cooperating with a pairof substantially identical oscillating blade assemblies 61 and 62. Theoscillating blade assemblies 61 and 62 are adapted to be oscillatedthrough suitable driving 'means by the motor 30 at a suitable speedwhich may be in excess of 8000 cycles per minute. Each of the bladeassemblies 61 and 62 includes a plurality of cutters or cutter blades63, individually referred to as 63a, 63b and 63c.

For the purpose of supporting the cutter blades 63 for oscillation,there are provided a pair of oscillating cutter shafts 65 and 66, eachcarrying a pair of U-shaped supports 67 and 68, respectively, best shownin FIGS. 1 and 6. The cutter shafts 65 and 66 are of rectangular orsquare cross section. The bight portions of the blade supports 67 and 68are provided with slots 64 and 69 respectively to receive and be securedto the respective shafts 65 and 66, while the legs thereof extendupwardly to define slotted blade support portions 67a, 67b, 68a, 68b ina manner well understood in the art, blades 63 being receivable inaligned slots in the support portions 67a, 67b, 68a and 68b. The cutterblades 63 are effectively identical and may be similar to those fullydescribed in either the above identified J epson et al. patent or Jepsonet al. application.

For the purpose of biasing the cutter blades 63 into shearing engagementwith the comb 60, there is provided for each blade support 67 and 68 atined spring member 70, best illustrated in FIG. 6. As illustrated eachspring member 70 is shaped like a short-handled three-tined fork havingthe short handle portion thereof secured to the respective shaft 65 or66 and with the three tines or spring fingers each extending into thepath of a different one of the blades 63 and consequently biasing theblades upwardly against the comb 60.

As best illustrated in FIG. 4, the comb 60 comprises a cutting surfaceformed of a very thin flexible material having a large number of hairreceiving openings. Since the cutting surface of the comb 60 is formedof relatively thin material, it tends to conform itself to the shape ofthe surface with which it is in contact and, therefore, must besupported by a suitable supporting structure or frame, generallydesignated at 74, comprising a plurality of parallel, double arcuateribs 74a, 74b, 74c, 74a, 74e, 74f, 74g and 7411 (FIG. 1) and spaced fromone another in a direction running along the longitudinal axis of thecutting blades 63. The end ribs 74a and 74h are effectively end framemembers and are somewhat stronger than the remaining ribs. The cuttingsurface portion of the comb 60 is suitably fastened at its outside edgesto the supporting frame 74 as by welding or other suitable means. Ifdesired, it may be removably secured. Moreover, in order to have thecutting surface follow the double arcuate contour of supporting frame 74with a central depressed portion (FIGS. 3 and 4) there is provided atubular comb tightener 75 which is held in place by U-shaped springretaining clips 76, best shown in FIG. 5. This comb tightener is similarto that disclosed and claimed in the above-mentioned copending Stahly etal. application.

For retaining the comb 60 in shearing relationship with the rest of thecutting head assembly 29, there is provided a comb lock spring 78 (FIG.3) clamped in place between the bail hanger 38 and the support 26 by thebail clamps 37. As illustrated, the comb lock spring 78 terminates indownwardly extending pivot flanges 780. A movable comb hinge plate 79has one edge releasably secured to one lower edge of the comb supportingframe 74. Moreover hinge plate 79 is hook-shaped as indicated at 79a onits other edge so as to make engagement with one of the downwardlydepending flanges 78a of the comb lock spring 78. A comb latch plate 80on the opposite side of the comb 60 from the hinge plate 79 is pivotallyrelated to the other pivot flange 78a on comb lock spring 78. Latchplate 80 is further provided with a centrally disposed latch member 80aextending through a suitable latch opening in the comb supporting frame74 thereby to latch the comb 60 in place as part of the cutting headassembly 29. The comb hinge plate 79 and comb latch plate 80 preferablyare similar to those more fully described in the prior mentioned Jepsonet a1. Patent No. 3,196,539.

To support the cutter shafts 65 and 66 for oscillation, each shaft isprovided adjacent each end thereof with suitable resilient mountingblocks 82 preferably bonded to the associated shaft, which blocks may beof the type more fully described in a copending Jepson application, Ser.No. 410,115, filed Nov. 1964, now Patent No. 3,244,916, and assigned tothe same assignee as the present application. As in such copendingapplication, the mounting blocks 82 are clamped securely into positionbetween support member 26 and end caps 24 and 25, suitable recesses forsuch mounting blocks being provided. As illustrated, the shafts 65 and66 are each provided with integral crank portions 65a and 66a,respectively (FIGS. 2 and 6), defined by offset projections of theshafts.

For the purpose of converting rotary motion of the motor armature 39 tooscillating motion of the cutter shafts 6S and 66, there is provided inaccordance with the present invention an improved connecting rod 84(FIGS. 1 and 2). The connecting rod 84 is generally fork-shaped with abifurcated portion defining two crank arms 84a, 84b, each receiving arespective one of the crank portions 65a, 66a of the respective cuttershafts 65 and 66 and a body portion 84c. The body portion 84c receivesthe crank pin 46 and is held assembled with the crank pin 46 by means ofa hairpin type lock spring 85. Because of the variation in spacingbetween the driven ends of the oscillating shafts 65 and 66, the arms84a, 84b on the connecting rod 84 must flex to accommodate thisvariation as the shafts 65 and 66 are oscillating. Accordingly theconnecting rod 84 is made of suitably resilient or springy material,such as molded nylon, and the arms 84a and 84b have a reducedcross-sectional area (FIG. 2) where they join with the body portion 840to provide the desired flex of the arms 84a, 84b.

For cutting longer hair such as trimming a moustache, sideburns and thelike, one of the end caps carries a trimming cutter assembly 87 (FIG. 1)driven by a projection from one of the cutter shafts 66. The trimmercutter assembly 87 may be identical with that described in the abovementioned Stahly et al. application and forms no part of the presentinvention. Accordingly the trimmer cuter assembly is not described inthe present application.

The twin cutter shafts driven by a single connecting rod simplifies thedrive of the double shaft head and provides a simple design which isinexpensive to manufacture. The single oscillating connecting rod canreplace two separate connecting rods, gears and pinion because of itsability to flex sufliciently to accommodate the variations in the shaftspacings of the cutter shafts as they oscillate. Moreover therectangular cross section of the cutter shafts 65 and 66 permits the useof simple blade supports 67 of formed metal pieces which may be merelyspot welded to the supporting shaft, and further permit the simple tinedblade springs 70 to be readily spot welded or otherwise secured to thecutter shafts.

While there has been shown and described a particular embodiment of thepresent invention, it will be apparent to those skilled in the art thatvarious changes and modifications may be made without departing from theinvention in its broader aspects and it is, therefore, contemplated inthe appended claims to cover all such changes and modifications as fallwithin the true spirit and scope of the present invention.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. An electric shaver comprising a shaving head unit including aperforated skin engaging member and a pair of oscillating cutter shaftseach carrying cutter blade means movable relative to said skin engagingmember,

' each of said cutter shafts being provided with an offset portiondefining a crank, a power unit including motor means having a driveprojection movable toward and away from said cutter shafts, and aunitary bifurcated connecting rod defining a body portion connected tosaid projection and a pair of arms each connected to a respective one ofsaid cranks and sufliciently resilient to permit flexing of said armsrelative to each other as said cranks oscillate.

2. An electric shaver as set forth in claim 1 wherein said motor meansis of the rotary type and said drive projection is eccentricallypositioned relative to the axis of rotation thereof to define a crankpin.

3. An electric shaver as set forth in claim 1 wherein said arms areprovided with reduced cross-sectional areas adjacent said body portionto provide greater resilience thereto.

4. An appliance comprising a driven unit including a pair of paralleldriven shafts each provided with an offset portion defining a crank, apower unit having a drive projection movable toward and away from saidcranks, and a unitary bifurcated connecting rod defining a body portionconnected to said drive projection and a pair of arms each connected toa respective one of said cranks and sufliciently resilient to permitflexing of said arms relative to each other as said cranks oscillate.

5. A shaver of the type having a uniformly curved comb and an elongatedcutter blade adapted to be moved along the inner side of said comb inshearing engagement therewith, the combination of a substantiallyrectangular shaft provided with spaced apart supports extending radiallytherefrom, each of said supports having a slot at the end thereof whichis remote from said shaft, said slots receiving said cutter blade, and apair of elongated springs each having one end thereof joined to saidshaft and the other end thereof in biasing engagement with said cutterblade to bias said cutter blade into engagement with said comb.

6. A shaver as set forth in claim 5 having a plurality of said cutterblades and wherein said supports are provided with a plurality of slots,the corresponding slots on each support receiving one of said cutterblades, and wherein said springs are each shaped like a short-handledmultitined fork having the handle portion thereof secured to said shaftand having said tines engaging and biasing a different one of saidcutter blades.

7. A shaver of the type having a uniformly curved comb and an elongatedcutter blade adapted to be moved along the inner side of said comb inshearing engagement therewith, the combination of a substantiallyrectangular shaft, a plurality of U-shaped supports having groove meansin their bight portions receiving said shaft, the legs of said supportsextending upwardly and provided with aligned slots to receive saidcutter blade, and spring means engaging said cutter blade biasing saidblade into shearing engagement with said comb.

8. A shaver as set forth in claim 7 having a plurality of said cutterblades, and wherein each of said legs is provided with a plurality ofaligned slots to receive respective ones of said blades.

9. An electric shaver comprising a power unit, a shaving head unitoperatively connected to said power unit and including a cutter supportmember, a comb frame carried by said support member defined by aplurality of parallel frame ribs spaced from one another along thelongitudinal axis of said shaving head unit and each formed by twojoining arcuate sections providing a recessed portion therebetween, aperforated skin engaging comb member fastened at its edges to said combframe, an elongated member defining a comb tightener positioned oversaid comb member along said recessed portion, tightening means biasingsaid member inwardly into said recessed portion to tighten said combmember over said comb frame to define a comb member having two joiningarcuate sections, and a pair of movable cutter members each includingblade means relatively movable against respective ones of the joiningarcuate sections of said comb member.

10. An electric shaver as set forth in claim 9 wherein said tighteningmeans is defined by a pair of U-shaped retaining clips, each engageablewith a respective end of said elongated member and secured beneath anend one of said frame ribs.

11. An electric shaver of the type comprising a casing and motive meanswithin said casing, a cutting head assembly associated with said casingincluding a pair of spaced parallel cutter shafts, a pluralityof bladesupporting means secured'to each shaft, and driving means forsimultaneously oscillating said shafts about their respectivelongitudinal axes.

References Cited 1 UNITED STATES PATENTS 1,655,151 1/1928,,' Lund ,74 4s2,178,151 10/1939 Wagar 2671 X 2,246,270 6/1941 Staak 2671X 2,308,0491/1943 Brull 3043.8 2,688,184 9/1954 JepSOn 30 43.9 2,858,607 11/1958Kane -3 30-436 2,982,020 5/1961 Bulova 61; a1. 30-439 3,206,850 9/1965Jepson 3043.9 3,262,335 7/1966 Heinlein et a1 a 74581 3,290,774 12/1966Schuessler 30 34.1

FOREIGN PATENTS 932,172 8/1955 Germany. 411,272 7/1945 Italy. MYRO N c.KRUSE, Primary Exdmir

